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Resolving Lifshitz Horizons

Description: Via the AdS/CFT correspondence, ground states of field theories at finite charge density are mapped to extremal black brane solutions. Studies of simple gravity + matter systems in this context have uncovered wide new classes of extremal geometries. The Lifshitz metrics characterizing field theories with non-trivial dynamical critical exponent z {ne} 1 emerge as one common endpoint in doped holographic toy models. However, the Lifshitz horizon exhibits mildly singular behaviour - while curvatur… more
Date: April 24, 2012
Creator: Harrison, Sarah; Kachru, Shamit; Wang, Huajia & /Stanford U., ITP /Stanford U., Phys. Dept. /SLAC
Partner: UNT Libraries Government Documents Department
open access

Experimental Evaluation of Multi-spacecraft Data Analysis Techniques in a Laboratory Plasma

Description: The Magnetic Reconnection Experiment (MRX)[1] has been utilized to assess the effectiveness of minimum variance analysis on the magnetic field (MVAB) and boundary-crossing time analysis (BCTA). The neutral sheet is swept, or jogged, in a controlled manner with respect to the stationary probes by pulsed internal coil currents. Magnetic field data from measurement points resembling data from multi-spacecraft flying though a reconnecting current sheet is used to check both techniques to deduce a p… more
Date: March 27, 2012
Creator: Yamada, Jongsoo Yoo and Masaaki
Partner: UNT Libraries Government Documents Department
open access

Advanced Production Surface Preparation Technology Development for Ultra-High Pressure Diesel Injection

Description: In 2007, An Ultra High Injection Pressure (UHIP) fueling method has been demonstrated by Caterpillar Fuel Systems - Product Development, demonstrating ability to deliver U.S. Environment Protection Agency (EPA) Tier 4 Final diesel engine emission performance with greatly reduced emissions handling components on the engine, such as without NOx reduction after-treatment and with only a through-flow 50% effective diesel particulate trap (DPT). They have shown this capability using multiple multi-c… more
Date: April 30, 2012
Creator: Grant, Marion B.
Partner: UNT Libraries Government Documents Department
open access

Power distributions in fresh and depleted LEU and HEU cores of the MITR reactor.

Description: The Massachusetts Institute of Technology Reactor (MITR-II) is a research reactor in Cambridge, Massachusetts designed primarily for experiments using neutron beam and in-core irradiation facilities. It delivers a neutron flux comparable to current LWR power reactors in a compact 6 MW core using Highly Enriched Uranium (HEU) fuel. In the framework of its non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used… more
Date: April 4, 2012
Creator: Wilson, E. H.; Horelik, N. E.; Dunn, F. E.; Newton, T. H., Jr.; Hu, L.; Stevens, J. G. et al.
Partner: UNT Libraries Government Documents Department
open access

PDC IC WELD FAILURE EVALUATION AND RESOLUTION

Description: During final preparations for start of the PDCF Inner Can (IC) qualification effort, welding was performed on an automated weld system known as the PICN. During the initial weld, using a pedigree canister and plug, a weld defect was observed. The defect resulted in a hole in the sidewall of the canister, and it was observed that the plug sidewall had not been consumed. This was a new type of failure not seen during development and production of legacy Bagless Transfer Cans (FB-Line/Hanford). Th… more
Date: April 16, 2012
Creator: Korinko, P.; Howard, S.; Maxwell, D. & Fiscus, J.
Partner: UNT Libraries Government Documents Department
open access

A High Resolution Monolithic Crystal, DOI, MR Compatible, PET Detector

Description: The principle objective of this proposal is to develop a positron emission tomography (PET) detector with depth-of-interaction (DOI) positioning capability that will achieve state of the art spatial resolution and sensitivity performance for small animal PET imaging. When arranged in a ring or box detector geometry, the proposed detector module will support <1 mm3 image resolution and >15% absolute detection efficiency. The detector will also be compatible with operation in a MR scanner t… more
Date: March 6, 2012
Creator: Miyaoka, Robert S
Partner: UNT Libraries Government Documents Department
open access

DX magnet requirements for p-Au operation

Description: This document addresses the question of moving the DX magnets for p-Au operations. First the beam geometry is addressed. Next, the beam sizes are covered. Finally, a conclusion is presented.
Date: January 19, 2012
Creator: Tepikian, S.; Trbojevic&#44 & D.
Partner: UNT Libraries Government Documents Department
open access

Optimization of the Transport Shield for Neutrinoless Double Beta-decay Enriched Germanium

Description: This document presents results of an investigation of the material and geometry choice for the transport shield of germanium, the active detector material used in 76Ge neutrinoless double beta decay searches. The objective of this work is to select the optimal material and geometry to minimize cosmogenic production of radioactive isotopes in the germanium material. The design of such a shield is based on the calculation of the cosmogenic production rate of isotopes that are known to cause inter… more
Date: April 15, 2012
Creator: Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.; Reid, Douglas J. & Fast, James E.
Partner: UNT Libraries Government Documents Department
open access

New Fabrication Method Improves the Efficiency and Economics of Solar Cells (Fact Sheet)

Description: Synthetic fabrication strategy optimizes the illumination geometry and transport properties of dye-sensitized solar cells. Using oriented titanium oxide (TiO{sub 2}) nanotube (NT) arrays has shown promise for dye-sensitized solar cells (DSSCs). High solar conversion efficiency requires that the incident light enters the cell from the photoelectrode side. However, for NT-based DSSCs, the light normally enters the cell through the counter electrode because a nontransparent titanium foil is typica… more
Date: July 1, 2012
Partner: UNT Libraries Government Documents Department
open access

Loop-to-loop coupling.

Description: This report estimates inductively-coupled energy to a low-impedance load in a loop-to-loop arrangement. Both analytical models and full-wave numerical simulations are used and the resulting fields, coupled powers and energies are compared. The energies are simply estimated from the coupled powers through approximations to the energy theorem. The transmitter loop is taken to be either a circular geometry or a rectangular-loop (stripline-type) geometry that was used in an experimental setup. Simp… more
Date: May 1, 2012
Creator: Warne, Larry Kevin; Lucero, Larry Martin; Langston, William L.; Salazar, Robert Austin; Coleman, Phillip Dale; Basilio, Lorena I. et al.
Partner: UNT Libraries Government Documents Department
open access

Numerical Homogenization on Approach for Stokesian Suspensions.

Description: In this technical report we investigate efficient methods for numerical simulation of active suspensions. The prototypical system is a suspension of swimming bacteria in a Newtonian fluid. Rheological and other macroscopic properties of such suspensions can differ dramatically from the same properties of the suspending fluid alone or of suspensions of similar but inactive particles. Elongated bacteria, such as E. coli or B. subtilis, swim along their principal axis, propelling themselves with t… more
Date: January 20, 2012
Creator: Haines, Brian M.; Berlyand, Leonid V. & Karpeev, Dmitry A.
Partner: UNT Libraries Government Documents Department
open access

Multilevel method for modeling large-scale networks.

Description: Understanding the behavior of real complex networks is of great theoretical and practical significance. It includes developing accurate artificial models whose topological properties are similar to the real networks, generating the artificial networks at different scales under special conditions, investigating a network dynamics, reconstructing missing data, predicting network response, detecting anomalies and other tasks. Network generation, reconstruction, and prediction of its future topolog… more
Date: February 24, 2012
Creator: Safro, I. M. (Mathematics and Computer Science)
Partner: UNT Libraries Government Documents Department
open access

Scoping analysis of the Advanced Test Reactor using SN2ND

Description: A detailed set of calculations was carried out for the Advanced Test Reactor (ATR) using the SN2ND solver of the UNIC code which is part of the SHARP multi-physics code being developed under the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program in DOE-NE. The primary motivation of this work is to assess whether high fidelity deterministic transport codes can tackle coupled dynamics simulations of the ATR. The successful use of such codes in a coupled dynamics simulation can impact… more
Date: July 26, 2012
Creator: Wolters, E.; Smith, M. & SC), (
Partner: UNT Libraries Government Documents Department
open access

Representing Range Compensators with Computational Geometry in TOPAS

Description: In a proton therapy beamline, the range compensator modulates the beam energy, which subsequently controls the depth at which protons deposit energy. In this paper, we introduce two computational representations of range compensator. One of our compensator representations, which we refer to as a subtraction solid-based range compensator, precisely represents the compensator. Our other representation, the 3D hexagon-based range compensator, closely approximates the compensator geometry. We have … more
Date: September 7, 2012
Creator: Iandola, Forrest N. & /Illinois U., Urbana /SLAC
Partner: UNT Libraries Government Documents Department
open access

Preconditioner and convergence study for the Quantum Computer Aided Design (QCAD) nonlinear poisson problem posed on the Ottawa Flat 270 design geometry.

Description: A numerical study aimed to evaluate different preconditioners within the Trilinos Ifpack and ML packages for the Quantum Computer Aided Design (QCAD) non-linear Poisson problem implemented within the Albany code base and posed on the Ottawa Flat 270 design geometry is performed. This study led to some new development of Albany that allows the user to select an ML preconditioner with Zoltan repartitioning based on nodal coordinates, which is summarized. Convergence of the numerical solutions com… more
Date: May 1, 2012
Creator: Kalashnikova, Irina
Partner: UNT Libraries Government Documents Department
open access

A Maximally Supersymmetric Kondo Model

Description: We study the maximally supersymmetric Kondo model obtained by adding a fermionic impurity to N = 4 supersymmetric Yang-Mills theory. While the original Kondo problem describes a defect interacting with a free Fermi liquid of itinerant electrons, here the ambient theory is an interacting CFT, and this introduces qualitatively new features into the system. The model arises in string theory by considering the intersection of a stack of M D5-branes with a stack of N D3-branes, at a point in the D3 … more
Date: February 17, 2012
Creator: Harrison, Sarah; Kachru, Shamit; Torroba, Gonzalo & /Stanford U., Phys. Dept. /SLAC
Partner: UNT Libraries Government Documents Department
open access

Methods for Quantifying Shallow-Water Habitat Availability in the Missouri River

Description: As part of regulatory requirements for shallow-water habitat (SWH) restoration, the U.S. Army Corps of Engineers (USACE) completes periodic estimates of the quantity of SWH available throughout the lower 752 mi of the Missouri River. To date, these estimates have been made by various methods that consider only the water depth criterion for SWH. The USACE has completed estimates of SWH availability based on both depth and velocity criteria at four river bends (hereafter called reference bends), … more
Date: April 9, 2012
Creator: Hanrahan, Timothy P. & Larson, Kyle B.
Partner: UNT Libraries Government Documents Department
open access

Adding a MOAB Geometry Interface to SHARP Structural Mechanics

Description: The authors briefly summarize the development of, and test experience with, an initial data interface between the structural mechanics code Diablo and the SHARP reactor simulation system data hub MOAB. That interface has been exercised both to write MOAB databases from Diablo, and then also to use such a database to read in part of a simulation definition for a subsequent Diablo execution. All enhancements are integrated into the central Diablo source repository. The SHARP software system for a… more
Date: May 28, 2012
Creator: Ferencz, R M & Hodge, N E
Partner: UNT Libraries Government Documents Department
open access

Plasma Synthesized Doped Boron Nanopowder for MgB2 Superconductors

Description: Under this program, a process to synthesize nano-sized doped boron powder by a plasma synthesis process was developed and scaled up from 20 gram batches at program start to over 200 grams by program end. Over 75 batches of boron nanopowder were made by RF plasma synthesis. Particle sizes were typically in the 20-200 nm range. The powder was synthesized by the reductive pyrolysis of BCl{sub 3} in hydrogen in an RF plasma. A wide range of process parameters were investigated including plasma powe… more
Date: March 26, 2012
Creator: Marzik, James V.
Partner: UNT Libraries Government Documents Department
open access

FY2012 Summary of Tasks Completed on Proteus-Thermal Work.

Description: PROTEUS is a suite of the neutronics codes, both old and new, that can be used within the SHARP codes being developed under the NEAMS program. Discussion here is focused on updates and verification and validation activities of the SHARP neutronics code, DeCART, for application to thermal reactor analysis. As part of the development of SHARP tools, the different versions of the DeCART code created for PWR, BWR, and VHTR analysis were integrated. Verification and validation tests for the integrat… more
Date: June 6, 2012
Creator: Lee, C.H. & Smith, M.A. (Nuclear Engineering Division)
Partner: UNT Libraries Government Documents Department
open access

Basics of Polar-Format algorithm for processing Synthetic Aperture Radar images.

Description: The purpose of this report is to provide a background to Synthetic Aperture Radar (SAR) image formation using the Polar Format (PFA) processing algorithm. This is meant to be an aid to those tasked to implement real-time image formation using the Polar Format processing algorithm.
Date: May 1, 2012
Creator: Doerry, Armin Walter
Partner: UNT Libraries Government Documents Department
open access

Letter to Russia

Description: Below is the referee report. It is not as bad as it seems at first. The manuscript has not been rejected. Instead, the referee is 'not recommending publication.' On the APS website, the status is 'with authors,' instead of 'not under consideration.' Thus, this manuscript is still alive, but we will need to work on it. Please take a look at what the referee says below and let me know how you would respond. I will do the same. Hopefully, we will be able to respond well and find a way for this man… more
Date: March 15, 2012
Creator: Tobin, J G
Partner: UNT Libraries Government Documents Department
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